ImpressCMS is multilanguage at its core. This means that you can manage content in multiple languages easily on your site. In order to do so, you also need to translate the user interface around your content. These packages will help you do that.
These language packs provide the translation of the interface of the ImpressCMS Core package. You can add the contents of these packages to your server before installing ImpressCMS, in order to have access to them from the beginning, or you can add the languages after that and make them available via the Admin Control Panel (ACP).
Language packs for modules are available in their own category.